Stub tools for use in unit testing
Stubble (a part of the Reahl development tools) is a collection of tools for writing stubs in unit tests. Stubble can be used independently of the Reahl web framework.
Using stubs allows one to decouple one unit test from real code unrelated to it - you write a fake class to take the place of a real one (which this test is not testing).
Stubble ensures, however, that the test will break should the interface of the stub differ from that of the real class it is a stub for.